Tropical spastic paraparesis (TSP) and other chronic‐progressive myelopathies have been clearly associated with increased serum and cerebrospinal fluid antibody titers to human T‐lymphotropic virus type I (HTLV‐I). However, little is known about the cellular immune function in TSP. In the present study, activated T lymphocytes were found in the peripheral blood of patients with TSP. Specifically, there were increased numbers of large CD3+ cells that also expressed HLA‐DR and interleukin‐2–receptor molecules. A significantly elevated spontaneous lymphoproliferative response was demonstrated in all patients tested. Generation of measles virus–specific cytotoxic T‐cell response was reduced in 4 of 4 patients. This was similar to previous findings in patients with multiple sclerosis. However, unlike multiple sclerosis, reduced generation of cytotoxic T‐cell response to influenza and mumps viruses was observed in 2 of 4 patients. These observations confirm further the strong association between TSP and an HTLV‐I–like virus and suggest that the observed abnormalities of the cellular immune response in TSP are related to infection of lymphocytes by the retrovirus.
ASJC Scopus subject areas
- Clinical Neurology